AMD's Radeon RX Vega 64 and RX Vega 56 graphics cards reviewed

AMD's Vega for gamers is finally here. The Radeon RX Vega 64 and RX Vega 56 mark AMD's return to the high end of the graphics-card world. After a long, long stretch wherein 2015's Radeon R9 Fury X and R9 Fury were asked to hold the fort against Nvidia's Pascal onslaught, the company is relieving them with what promises to be competition for Nvidia's long-dominant GeForce GTX 1080 and GeForce GTX 1070.

The Vega 10 GPU that's riding in on those cards is a massive and massively complex piece of silicon. It packs 12.5 billion transistors into a 486 mm² die fabricated on GlobalFoundries' 14nm LPP FinFET process. (For comparison, the Nvidia GP102 chip aboard the GTX 1080 Ti and friends is a similarly massive 12 billion transistors on a 471 mm² die.) The card's compute resources are organized into 64 "Next-gen Compute Units." Each of these hosts 64 stream processors for a total of 4096. The full Vega 10 chip has 256 texture units and 64 ROPs, too.

While the basic organization of Vega 10 may sound similar to Fiji before it, the similarities largely end at those broad outlines. I would love to explore Vega's many changes and capabilities in more depth, but when you have two days and change to review two brand-new graphics cards in the wake of testing and writing for a CPU review, stuff has to be left on the cutting-room floor, and a deep dive on Vega's new talents is one of them. We've known broadly what the new bits of Vega would be since January, however, so my architecture introduction is as good a place as any to start if you need to catch up. I'll be trying to add more information to this article as time goes on, but AMD should have a white paper available soon with full architectural details if you want to know much, much more.

The Radeon RX Vega 64 and RX Vega 56
The implementations of the Vega 10 GPU that will be available to consumers were revealed at SIGGRAPH a couple weeks ago, but to recap, AMD will be selling the fully-enabled Vega 10 GPU aboard the Radeon RX Vega 64 in both air- and liquid-cooled varieties. The Radeon Vega 56, on the other hand, loses eight NCUs to the world's tiniest chainsaw, and it'll only be available as an air-cooled card in its reference form. Curiously, AMD left all 64 ROPs intact on both the RX Vega 64 and RX Vega 56, meaning the cuts to the 56 may hurt less than they otherwise might.

GPU
base
clock
(MHz)

GPU
boost
clock
(MHz)

ROP
pixels/
clock

Texels
filtered/
clock

Shader
pro-
cessors

Memory
path
(bits)

Memory
bandwidth

Memory
size

Board
power

GTX 970

1050

1178

56

104

1664

224+32

224 GB/s

3.5+0.5GB

145W

GTX 980

1126

1216

64

128

2048

256

224 GB/s

4 GB

165W

GTX 980 Ti

1002

1075

96

176

2816

384

336 GB/s

6 GB

250W

Titan X (Maxwell)

1002

1075

96

192

3072

384

336 GB/s

12 GB

250W

GTX 1070

1506

1683

64

120

1920

256

259 GB/s

8GB

150W

GTX 1080

1607

1733

64

160

2560

256

320 GB/s

8GB

180W

GTX 1080 Ti

1480

1582

88

224

3584

352

484 GB/s

11GB

250W

Titan Xp

1480?

1582

96

240

3840

384

547 GB/s

12GB

250W

R9 Fury X

---

1050

64

256

4096

1024

512 GB/s

4GB

275W

Radeon RX Vega 64
(air-cooled)

1247

1546

64

256

4096

2048

484 GB/s

8GB

295W

Radeon RX Vega 64
(liquid-cooled)

1406

1677

64

256

4096

2048

484 GB/s

8GB

345W

Radeon RX Vega 56

1156

1471

64

224

3584

2048

410 GB/s

8GB

210W

Both cards also ship with 8GB of HBM2 memory on board. That memory communicates with the Vega 10 chip across a 2048-bit bus. AMD doesn't disclose as much, but on the RX Vega 64 cards, that HBM2 runs at an effective rate of 1890 MT/s, and on the RX Vega 56, it runs at about 1600 MT/s.

Peak pixel
fill rate
(Gpixels/s)

Peak
bilinear
filtering
int8/fp16
(Gtexels/s)

Peak
rasterization
rate
(Gtris/s)

Peak
shader
arithmetic
rate
(tflops)

Memory
bandwidth
(GB/s)

Asus R9 290X

67

185/92

4.2

5.9

346

Radeon R9 295 X2

130

358/179

8.1

11.3

640

Radeon R9 Fury X

67

269/134

4.2

8.6

512

GeForce GTX 780 Ti

37

223/223

4.6

5.3

336

Gigabyte GTX 980

85

170/170

5.3

5.4

224

GeForce GTX 980 Ti

95

189/189

6.5

6.1

336

GeForce Titan X

103

206/206

6.5

6.6

336

GeForce GTX 1070

108

202/202

5.0

7.0

259

GeForce GTX 1080

111

277/277

6.9

8.9

320

GeForce GTX 1080 Ti

139

354/354

9.5

11.3

484

GeForce Titan X (Pascal)

147

343/343

9.2

11.0

480

Radeon RX Vega 64 (air)

99

396/198

6.2

12.7

484

Radeon RX Vega 64 (liquid)

107

429/215

6.7

13.7

484

Radeon RX Vega 56

94

330/165

5.9

10.5

410

We didn't have time (yet) ahead of publication to run our fancy Beyond3D test suite, so here are some potential peak rates for the RX Vega family. Compared to the GTX 1080, the RX Vega 64s trail slightly in pixel fill and peak rasterization rates, but they bring a prodigious array of shader and texturing power to the table, along with much higher memory bandwidth. The RX Vega 56 similarly trails and trounces the GTX 1070 in these theoretical peak rates. Our tests will tease out whether those theoretical victories translate into real performance shortly.

AMD's reference design for both the air-cooled RX Vega 64 and RX Vega 56 uses the same black shroud with an axial fan exhausting air directly out of the rear of the card. While this design may bear some similarities to the Radeon RX 480 before it, they're ony skin-deep. The shroud on this card is mostly metal and features a full metal backplate, as well. The Radeon logo on the side of the card lights up with red LEDs when the card is on.

One neat little touch from the R9 Fury X returns on board the RX Vegas: the "GPU Tach." This line of red LEDs (or blue, if you flip a DIP switch) will show you your GPU's occupancy, presuming you can see it from your desk or other site of sitting. The LEDs can also be turned off.

The Radeon RX Vega 56 will list for $399, or $20 more than the GTX 1070's original $379 suggested price. The RX Vega 64 air-cooled card will sticker for $499, or the same as the GTX 1080's most recent suggested price. Both cards are also available as limited editions and as parts of "Radeon Packs," which we described in more detail in our RX Vega reveal. We've been talking about RX Vega for ages, so now it's time to shut up and share performance numbers.